Java annotation: Difference between revisions

Revision as of 13:40, 16 February 2006

Revision as of 18:27, 16 February 2006

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In [[programming]] a '''Java annotationsannotation''' is a way of adding [[metadata]] to Java [[source code]] that is available to the programmer at [[run-time]].

Java annotations can be added to program elements such as classes, methods, fields, parameters, local variables, and packages. Unlike tags added to Java documentation and processed with tools such as [[XDoclet]], Java annotations are compleatly acessible to the programmer while the software is running using [[reflection (programming)|reflection]].

==History of Java annotation==

Java annotations were introduced to the Java Community Process as JSR-175 in [[2002]] and approved in September [[2004]]. Annotations became available with the [[JDK]] version 1.5. The feature was added to the Java language through the JSR-175 specification.

==How Java annotations are processed==

TheWhen compilerJava cansource storecode is compiled, the Java compiler stores annotation metadata in the class files. Later, the [[VMJVM]] or other programs can look for the metadata to determine how to interact with the program elements or change their behavior.

==Syntax of annotation==

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==Pros of using Java annotations==

Annotations allow the programmer to declare in their source code how the software should behave. It is an example of how declairativedeclarative programming constructs can be added to a procedural lanaguagelanguage.

==Cons of using Java annotations==